Specimen holder assembly



June 3, 1947.

Filed Dec. 50,1944

INVENTOR. PERRY C. SMITH FRANK E. RUNGE EDMlaD G. DORNF'ELD BY z ATTORNEY Patented June 3, 1947 SPECIMEN HOLDER ASSEMBLY Perry 0. Smith, Moorestown, Frank E. Runge, Haddon Heights, and Edmund G. D'ornfeld, Audubon, N. J assignors to Radio Corporation of America, acorporation of Delaware Application DecemberBO, 1944, Serial No."570 ,660

7 Claims. l l The present invention relates to electron microscopes and more particularly to an improvement in specimen holders.

Some of the objects of the present invention are: to provide an improved specimen holder; to provide a novel stage and specimen holder assembly; to provide a mounting for a specimenholder wherein provision is made for tilting the specimen holder to obtain stereoscopic effects; to provide a readilydemountable specimen holder; to provide a specimen chamber, specimen holder, and stage assembly wherein the holder is readily accessible for changing specimens or adjusting to a selected position with reference to the axis of the'column; to provide means whereby a'specimen holder can be swung about its longitudinalaxis through a predetermined angle to permit portions of the front and one side of the specimen to 'be viewed or photographed; and to provide other improvementsas will hereinafter appear.

In theaccompanying drawings, Fig. 1 represents a transverse section of the object or specimen chamberof an-electron microscope showing a specimen holder and .stageassembly embodying one form of the present invention; Fig. 2 represents a side elevation of one form of specimen holderof'thepresentinvention; Fig. 3 represents a front elevation of the same; Fig. 4 represents a bottom plan on line 4-'4 of Fig. 2; Fig. 5 represents a rear elevation of the microscope stage with the specimen holder removed; Fig. 6 represents a planof the stage with the-specimen holder removed; and Fig. 7 represents a detail of the stage indent portion of the stage from which the specimen holder is-suspended and angularly positioned.

Referring to the drawings, one form of the specimen holder of the invention comprises a body 10 having-a relatively longelongated leg I l at one end and arelatively "short leg I2 at the other end, the two legs paralleling each other,

and forming with the body a seat to receive a portion of the stage l3 as will be later explained. The body l0 also includes a relatively thin handle l4 having a hole I5 to receive a finger or suitable tool for lifting the holder. A through hole [6 traverses the leg I I and serves to mount the specimen unit IT. The face l8 of the leg II is arcuate in cross-section in order to provide for an angular swing of the leg I I about its longitudinal axis.

For mounting the holder upon the stage [3 in a rigid and stable manner, the rear face of the stage I3 is formed with a diametrically disposed groove 20 of arcuate cross-section complemental to the arcuate face H! of the leg II. A flange 2| extends outwardly from the stage 'a distance substantially equal to the width of the seat, heretofore referred to asformed by the legs H and". Thus, the holder can he interfit with the stage by sliding the leg ll inwardly along the groove 2|] until the body part seats upon the edge portion of thestage and "the shortleg l2 abuts the outer face of the :fiange 21.

In order to anchor the specimen end'of the holder, :a spring 22 :of generally U-sh'ape is carried by the stage 1 3 and is arranged in'the path of the end of the leg l l in such a manner that the bringing of the holder into position causes its tapered end to expandthe spring 22 and snap it into a notch 23 in the leg "H to thereby lock the parts together with such aade'g-ree 'of resilience thattheileg H c'an'beiturnedto any onesof several angular positions. When the holder is thus suspended from the edge of the stag'e andgripped by the flexible springLinterlock, the specimen is then located and held in-coincidence with the longitudinalor beam axisof the microscope.

As a further means of interlocking the :holder to'the stage, an indent plate "24 is mounted as an insert upon the flange 2| and has an outer curved face2'5 concentric with respect to'thestage groove Zlland provided, in the present instance, with five notches, one 26 at the center corresponding to the normal viewing position of. the holder, namely when the holder locates the axisof the specimen unit coincident with the axis of the column, and two, 2 1 and 28, at each side of the center corresponding respectively to asymmetrical viewing position of the holder. A latching pin 30 is mounted 'forsliding movement transversely-of theshort leg 12 insuch a position as to engage any oneof the notches 26, 21 and 28, according to the selected position of the holder,

and is of greater length than 'thewidthof the leg l2. The-outer projecting end of the pin 30 is reduced in diameter to enter a hole in a strip spring 32 which is secured to the leg l2 by a screw 33. Thus, the pressure of the spring 32 on the shoulder of the pin 30 holds the latter firmly in any selected notch but can readily yield to unlatch the holder from the indent plate 2'! under a manual turning of the holder. For normal or symmetrical viewing of the specimen, the pin 30 is latched in the notch 26, but for stereoscopic viewing the holder may be turned through an angle determined by two positions at either side of the notch 26, and so locked in notch 21 for a small angular turn or in notch 28 for a larger angular turn. In this manner the specimen can be viewed or photographed at a selected angle to one side of the center position and then at the corresponding angle at the opposite side of this center position.

By the present novel construction, the holder has its adjusting handle l4 located in close proximity to the access opening 33 which communicates with the specimen chamber and is normally sealed by the closure 34 under atmospheric pressure. By breaking the vacuum in the specimen chamber the closure 34 can be removed and the specimen holder then adjusted to a selected position or removed to change specimens.

We claim as our invention: 7 a

1. In an electron microscope of the type having a column with its axis alined with the electron beam of an electron gun, the combination of a stage having an opening arranged in coincidence with said axis, said stage having an arcuate groove therein, a specimen holder slidably mounted in said groove and normally positioning a specimen opposite said stage opening, said holder having a face complementally curved both to ride linearly in said groove and to turn angularly about its longitudinal axis, and means to anchor said holder in assembled position and also in an angular position.

7 2. In an electron microscope of the type having a column with its axis alined with the electron beam of an electron gun, the combination of a stage having an opening arranged in coincidence with said axis, said stage having an arcuate groove therein, a specimen holder slidably mounted in said groove and normally positioning a specimen opposite said stage opening, aid holder having a face complementally curved both toride linearly in said groove and to turn angularly about its longitudinal axis, and yielding means for removably attaching one end of said holder to said stage.

'3. In an electron microscope of the type having a column with its axis alined with the electron beam of an electron gun, the combination of a stage having anopening arranged in coincidence with said axis, said stage having an arcuate groove therein, a specimen holder slidably mounted in said groove and normally positioning a specimen; opposite said stage opening, said holder having a face complementally curved both to ride linearly in said groove and to turn angularly about its longitudinal axis, yielding means for removably attaching one end of said holder to said stage, and means for latching the opposite end of said holder to said stage in any one of a'number of holder angular positions.

.4, In an electron microscope of the type havingacolumn with its axis alined with the electron beam of an electron gun, the combination of a stage having an opening arranged in coincidence with said axis, a specimen holder comprising a body having two legs spaced apart to form a seat to receive the rim of said stage, one

of said legs in assembled condition locating a specimen in alinement with said stage opening, an indent plate carried by said stage having notches juxtaposed to the other leg, and a spring pressed pin in said last mentioned leg for latching engagement with an opposite notch.

5. In an electron microscope of the type having a column with its axis alined with the electron beam of an electron gun, the combination of a stage havin an opening arranged in coincidence with said axis, a specimen holder comprising a body having a long leg and a short leg spaced apart to straddle a portion of said stage to suspend said holder slidably upon said stage, said long leg in assembled condition locating a specimen in alinement with said stage opening, means permitting said holder to turn relative to said stage about said' long leg as an axis, and means between said short leg and said stage for latching said holder in any one of a number of positions.

6. In an electron microscope of the type hav-: ing a column with its axis alined with the elec-1 tron beam of an electron gun, the combination of a stage having an opening arranged in coincidence with said axis, a specimen holder slidably mounted on said stage and normally positioning a specimen opposite said stage opening, and juxtaposed curved contactin surfaces between said holder and said stage, whereby said holder can be turned to obtain stereoscopic views of saidspecimen. 7

7. In an electron microscope of the-type'having a column with its axis'alined with the electron beam of an electron gun, the combination of a stage having an opening arranged in coincidence with said axis, a specimen holder slidably mounted on said stage and normallyposisitioning a specimen opposite said stage opening,

juxtaposed curved contactin surfaces between,

said holder and said stage, whereby said'holder can be turned to obtain stereoscopic views of said specimen, and spring means for connecting said holder with said stage. 45

PERRY 0. SMITH. FRANK E. RUNGE. EDMUND G. DORNFELD.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED sTATEs PATENTS Marton Nov. 12, 1940 Date 

